66 BelAir Stock Elim. Car

Alan Roehrich · 10-21-2009, 08:52 PM

The problem I see with the oval port 427 is that the cam is already small for a 396 with those heads. A 427 isn't really much more of a torque type engine than a 396.

I'd be concerned about getting the cylinders full enough on the 427 to make torque. With a 454 oval port engine, the longer stroke pulls on the port for a longer period of time.

A 427 only pulls on it for the same amount of time as a 396. The larger cylinder bore doesn't really help much either, as the valves are small enough that the 396 bore does not really shroud them. You have a little more piston area pulling a little hard on the port and the valve, but for the same period of time, so adding duration may not help.

10-21-2009, 08:52 PM	#25
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,118 Likes: 1,577 Liked 1,837 Times in 417 Posts	Re: 66 BelAir Stock Elim. Car The problem I see with the oval port 427 is that the cam is already small for a 396 with those heads. A 427 isn't really much more of a torque type engine than a 396. I'd be concerned about getting the cylinders full enough on the 427 to make torque. With a 454 oval port engine, the longer stroke pulls on the port for a longer period of time. A 427 only pulls on it for the same amount of time as a 396. The larger cylinder bore doesn't really help much either, as the valves are small enough that the 396 bore does not really shroud them. You have a little more piston area pulling a little hard on the port and the valve, but for the same period of time, so adding duration may not help. __________________ Alan Roehrich 212A G/S